iOS: Setting up a system-provided text input control

3 files changed, 176 insertions, 5 deletions

diff --git a/src/ios.h b/src/ios.h
index 85177409..2908d833 100644
--- a/src/ios.h
+++ b/src/ios.h
@@ -61,3 +61,23 @@ iBool   isPaused_AVFAudioPlayer     (const iAVFAudioPlayer *);
 
 void    clearNowPlayingInfo_iOS     (void);
 void    updateNowPlayingInfo_iOS    (void);
+
+/*----------------------------------------------------------------------------------------------*/
+
+enum iSystemTextInputFlags {
+    multiLine_SystemTextInputFlags         = iBit(1),
+    returnGo_SystemTextInputFlags          = iBit(2),
+    returnSend_SystemTextInputFlags        = iBit(3),
+    disableAutocorrect_SystemTextInputFlag = iBit(4),
+    alignRight_SystemTextInputFlag         = iBit(5),
+};
+
+iDeclareType(SystemTextInput)
+iDeclareTypeConstructionArgs(SystemTextInput, int flags)
+
+void    setRect_SystemTextInput  (iSystemTextInput *, iRect rect);
+void    setText_SystemTextInput  (iSystemTextInput *, const iString *text);
+void    setFont_SystemTextInput  (iSystemTextInput *, int fontId);
+void    setTextChangedFunc_SystemTextInput  (iSystemTextInput *, void (*textChangedFunc)(iSystemTextInput *, void *), void *);
+
+const iString * text_SystemTextInput    (const iSystemTextInput *);
diff --git a/src/ios.m b/src/ios.m
index b46fb8dc..be1e644f 100644
--- a/src/ios.m
+++ b/src/ios.m
@@ -60,6 +60,8 @@ static UIViewController *viewController_(iWindow *window) {
     return NULL;
 }
 
+static void notifyChange_SystemTextInput_(iSystemTextInput *);
+
 /*----------------------------------------------------------------------------------------------*/
 
 API_AVAILABLE(ios(13.0))
@@ -159,9 +161,10 @@ API_AVAILABLE(ios(13.0))
 
 /*----------------------------------------------------------------------------------------------*/
 
-@interface AppState : NSObject<UIDocumentPickerDelegate> {
+@interface AppState : NSObject<UIDocumentPickerDelegate, UITextFieldDelegate> {
     iString *fileBeingSaved;
     iString *pickFileCommand;
+    iSystemTextInput *sysCtrl;
 }
 @property (nonatomic, assign) BOOL isHapticsAvailable;
 @property (nonatomic, strong) NSObject *haptic;
@@ -175,9 +178,18 @@ static AppState *appState_;
     self = [super init];
     fileBeingSaved = NULL;
     pickFileCommand = NULL;
+    sysCtrl = NULL;
     return self;
 }
 
+-(void)setSystemTextInput:(iSystemTextInput *)sys {
+    sysCtrl = sys;
+}
+
+-(iSystemTextInput *)systemTextInput {
+    return sysCtrl;
+}
+
 -(void)setPickFileCommand:(const char *)command {
     if (!pickFileCommand) {
         pickFileCommand = new_String();
@@ -256,6 +268,21 @@ didPickDocumentsAtURLs:(NSArray<NSURL *> *)urls {
 -(void)keyboardOffScreen:(NSNotification *)notification {
     setKeyboardHeight_MainWindow(get_MainWindow(), 0);
 }
+
+- (BOOL)textFieldShouldReturn:(UITextField *)textField {
+    SDL_Event ev = { .type = SDL_KEYDOWN };
+    ev.key.keysym.sym = SDLK_RETURN;
+    SDL_PushEvent(&ev);
+    printf("Return pressed\n");
+    return NO;
+}
+
+- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
+    iSystemTextInput *sysCtrl = [appState_ systemTextInput];
+    notifyChange_SystemTextInput_(sysCtrl);
+    return YES;
+}
+
 @end
 
 static void enableMouse_(iBool yes) {
@@ -607,3 +634,85 @@ iBool isStarted_AVFAudioPlayer(const iAVFAudioPlayer *d) {
 iBool isPaused_AVFAudioPlayer(const iAVFAudioPlayer *d) {
     return d->state == paused_AVFAudioPlayerState;
 }
+
+/*----------------------------------------------------------------------------------------------*/
+
+struct Impl_SystemTextInput {
+    void *ctrl;
+    void (*textChangedFunc)(iSystemTextInput *, void *);
+    void *textChangedContext;
+};
+
+iDefineTypeConstructionArgs(SystemTextInput, (int flags), flags)
+
+#define REF_d_ctrl  (__bridge UITextField *)d->ctrl
+
+void init_SystemTextInput(iSystemTextInput *d, int flags) {
+    d->ctrl = (void *) CFBridgingRetain([[UITextField alloc] init]);
+    UITextField *field = REF_d_ctrl;
+    // TODO: Use the right font:  https://developer.apple.com/documentation/uikit/text_display_and_fonts/adding_a_custom_font_to_your_app?language=objc
+    [[viewController_(get_Window()) view] addSubview:REF_d_ctrl];
+    if (flags & returnGo_SystemTextInputFlags) {
+        [field setReturnKeyType:UIReturnKeyGo];
+    }
+    if (flags & returnSend_SystemTextInputFlags) {
+        [field setReturnKeyType:UIReturnKeySend];
+    }
+    if (flags & disableAutocorrect_SystemTextInputFlag) {
+        [field setAutocorrectionType:UITextAutocorrectionTypeNo];
+        [field setAutocapitalizationType:UITextAutocapitalizationTypeNone];
+        [field setSpellCheckingType:UITextSpellCheckingTypeNo];
+    }
+    if (flags & alignRight_WidgetFlag) {
+        [field setTextAlignment:NSTextAlignmentRight];
+    }
+    [field setDelegate:appState_];
+    [field becomeFirstResponder];
+    d->textChangedFunc = NULL;
+    d->textChangedContext = NULL;
+    [appState_ setSystemTextInput:d];
+}
+
+void deinit_SystemTextInput(iSystemTextInput *d) {
+    [appState_ setSystemTextInput:nil];
+    [REF_d_ctrl removeFromSuperview];
+    d->ctrl = nil; // TODO: Does this need to be released??
+}
+
+void setText_SystemTextInput(iSystemTextInput *d, const iString *text) {
+    [REF_d_ctrl setText:[NSString stringWithUTF8String:cstr_String(text)]];
+    [REF_d_ctrl selectAll:nil];
+}
+
+void setFont_SystemTextInput(iSystemTextInput *d, int fontId) {
+    int height = lineHeight_Text(fontId);
+    UIFont *font = [UIFont systemFontOfSize:0.65f * height / get_Window()->pixelRatio];
+    [REF_d_ctrl setFont:font];
+}
+
+const iString *text_SystemTextInput(const iSystemTextInput *d) {
+    return collectNewCStr_String([[REF_d_ctrl text] cStringUsingEncoding:NSUTF8StringEncoding]);;
+}
+
+void setRect_SystemTextInput(iSystemTextInput *d, iRect rect) {
+    const iWindow *win = get_Window();
+    CGRect frame;
+    frame.origin.x = rect.pos.x / win->pixelRatio;
+    frame.origin.y = (rect.pos.y - gap_UI + 2) / win->pixelRatio;
+    frame.size.width = rect.size.x / win->pixelRatio;
+    frame.size.height = rect.size.y / win->pixelRatio;
+    [REF_d_ctrl setFrame:frame];
+}
+
+void setTextChangedFunc_SystemTextInput(iSystemTextInput *d,
+                                        void (*textChangedFunc)(iSystemTextInput *, void *),
+                                        void *context) {
+    d->textChangedFunc = textChangedFunc;
+    d->textChangedContext = context;
+}
+
+static void notifyChange_SystemTextInput_(iSystemTextInput *d) {
+    if (d && d->textChangedFunc) {
+        d->textChangedFunc(d, d->textChangedContext);
+    }
+}
diff --git a/src/ui/inputwidget.c b/src/ui/inputwidget.c
index bd9b63b5..bb3851df 100644
--- a/src/ui/inputwidget.c
+++ b/src/ui/inputwidget.c
@@ -40,6 +40,11 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
 #   include "macos.h"
 #endif
 
+#if defined (iPlatformAppleMobile)
+#   include "ios.h"
+#   define LAGRANGE_ENABLE_SYSTEM_INPUT 1
+#endif
+
 static const int    refreshInterval_InputWidget_ = 512;
 static const size_t maxUndo_InputWidget_         = 64;
 static const int    unlimitedWidth_InputWidget_  = 1000000; /* TODO: WrapText disables some functionality if maxWidth==0 */
@@ -233,6 +238,7 @@ struct Impl_InputWidget {
     void *          validatorContext;
     iString *       backupPath;
     int             backupTimer;
+    iSystemTextInput *sysCtrl;
 };
 
 iDefineObjectConstructionArgs(InputWidget, (size_t maxLen), maxLen)
@@ -721,10 +727,12 @@ void init_InputWidget(iInputWidget *d, size_t maxLen) {
     d->buffered = NULL;
     d->backupPath = NULL;
     d->backupTimer = 0;
+    d->sysCtrl = NULL;
     updateMetrics_InputWidget_(d);
 }
 
 void deinit_InputWidget(iInputWidget *d) {
+    delete_SystemTextInput(d->sysCtrl);
     if (d->backupTimer) {
         SDL_RemoveTimer(d->backupTimer);
     }
@@ -953,6 +961,9 @@ void setText_InputWidget(iInputWidget *d, const iString *text) {
     iString *nfcText = collect_String(copy_String(text));
     normalize_String(nfcText);
     splitToLines_(nfcText, &d->lines);
+    if (d->sysCtrl) {
+        setText_SystemTextInput(d->sysCtrl, nfcText);
+    }
     iAssert(!isEmpty_Array(&d->lines));
     iForEach(Array, i, &d->lines) {
         updateLine_InputWidget_(d, i.value); /* count number of visible lines */
@@ -1008,6 +1019,16 @@ iLocalDef iBool isEditing_InputWidget_(const iInputWidget *d) {
     return (flags_Widget(constAs_Widget(d)) & selected_WidgetFlag) != 0;
 }
 
+static void contentsWereChanged_InputWidget_(iInputWidget *);
+
+#if defined (LAGRANGE_ENABLE_SYSTEM_INPUT)
+void systemInputChanged_InputWidget_(iSystemTextInput *sysCtrl, void *widget) {
+    iInputWidget *d = widget;
+    splitToLines_(text_SystemTextInput(sysCtrl), &d->lines);
+    contentsWereChanged_InputWidget_(d);
+}
+#endif
+
 void begin_InputWidget(iInputWidget *d) {
     iWidget *w = as_Widget(d);
     if (isEditing_InputWidget_(d)) {
@@ -1016,7 +1037,18 @@ void begin_InputWidget(iInputWidget *d) {
     }
     invalidateBuffered_InputWidget_(d);
     setFlags_Widget(w, hidden_WidgetFlag | disabled_WidgetFlag, iFalse);
+    setFlags_Widget(w, selected_WidgetFlag, iTrue);
     mergeLines_(&d->lines, &d->oldText);
+#if defined (LAGRANGE_ENABLE_SYSTEM_INPUT)
+    d->sysCtrl = new_SystemTextInput((d->inFlags & isUrl_InputWidgetFlag ? disableAutocorrect_SystemTextInputFlag : 0) |
+                                     (!cmp_String(id_Widget(w), "url") ? returnGo_SystemTextInputFlags : 0) );
+//                                     (flags_Widget(w) & alignRight_WidgetFlag ? alignRight_SystemTextInputFlag : 0));
+    setFont_SystemTextInput(d->sysCtrl, d->font);
+    setRect_SystemTextInput(d->sysCtrl, contentBounds_InputWidget_(d));
+    setText_SystemTextInput(d->sysCtrl, &d->oldText);
+    setTextChangedFunc_SystemTextInput(d->sysCtrl, systemInputChanged_InputWidget_, d);
+    return;
+#endif
     if (d->mode == overwrite_InputMode) {
         d->cursor = zero_I2();
     }
@@ -1025,7 +1057,6 @@ void begin_InputWidget(iInputWidget *d) {
         d->cursor.x = iMin(d->cursor.x, cursorLine_InputWidget_(d)->range.end);
     }
     SDL_StartTextInput();
-    setFlags_Widget(w, selected_WidgetFlag, iTrue);
     showCursor_InputWidget_(d);
     refresh_Widget(w);
     startOrStopCursorTimer_InputWidget_(d, iTrue);
@@ -1048,15 +1079,22 @@ void end_InputWidget(iInputWidget *d, iBool accept) {
         /* Was not active. */
         return;
     }
-    enableEditorKeysInMenus_(iTrue);
-    if (!accept) {
+    if (d->sysCtrl) {
+        if (accept) {
+            splitToLines_(text_SystemTextInput(d->sysCtrl), &d->lines);
+        }
+        delete_SystemTextInput(d->sysCtrl);
+        d->sysCtrl = NULL;
+    }
+    else if (!accept) {
         /* Overwrite the edited lines. */
         splitToLines_(&d->oldText, &d->lines);
+        SDL_StopTextInput();
     }
+    enableEditorKeysInMenus_(iTrue);
     d->inFlags |= needUpdateBuffer_InputWidgetFlag;
     d->inFlags &= ~isMarking_InputWidgetFlag;
     startOrStopCursorTimer_InputWidget_(d, iFalse);
-    SDL_StopTextInput();
     setFlags_Widget(w, selected_WidgetFlag | keepOnTop_WidgetFlag | touchDrag_WidgetFlag, iFalse);
     const char *id = cstr_String(id_Widget(as_Widget(d)));
     if (!*id) id = "_";
@@ -2324,6 +2362,10 @@ static void draw_InputWidget_(const iInputWidget *d) {
                             isFocused ? gap_UI / 4 : 1,
                             isFocused ? uiInputFrameFocused_ColorId
                                       : isHover ? uiInputFrameHover_ColorId : uiInputFrame_ColorId);
+    if (d->sysCtrl) {
+        drawChildren_Widget(w);
+        return;
+    }
     setClip_Paint(&p, adjusted_Rect(bounds, init_I2(d->leftPadding, 0),
                                     init_I2(-d->rightPadding, w->flags & extraPadding_WidgetFlag ? -gap_UI / 2 : 0)));
     const iRect contentBounds = contentBounds_InputWidget_(d);